Superheater



March 4 1924. I 1,485,941

\ W. WULF .SUPBRHEATER Filed Oct. 27 1920 I v I V Ufinesseg:

Patented Mar. 4, 1924.

UNITED rarestoar-rs.

WILHELM WULF, OF NEUMUNSTER, GERMANY, ASSIGNOR T0 EDELDAMPF-GESELL- SCHAFT M. B. 11., OF HAMBURG, GERMANY.

SUPERHEATER.

Application filed October 27, 1920. Serial No. 420,051.

To all whom it may concern:

Be it known that I, WILHTJLM lVULr, a citizen of the German Republic, and resident of Neumunster, Germany, have invented a certain new and useful Superheater (for which I have filed an application in Germany Oct. 18, 1919), of which the following is a specification.

This invention relates to superheating tube-heads which are intended for use in connection with the usual superheating tubes located in the smoke-tubes of tubular boilers. These superheating-tube heads are located at the furnace end of the superheating tubes and connect them with each other, forming, thus, substitutes for the usual bends. Whilst, however, the heating surface of the usual bends is very small and practically insignificant, the heating surface of the novel superheating head is comparatively very large, and within it are formed two spirally shaped steam passages which provide a comparatively long way for the steam just in the hottest part of the smoke tube. The degree of superheating of the steam is, by this means, considerably increased.

In order to make my invention more clear, I refer to the accompanying drawing, in which similar letters denote similar parts throughout the several views, and in which:

Figure 1 is a longitudinal section through a locomotive boiler provided with superheating elements having tube-heads of the kind in question, the middle portion of the tubular boiler being broken away. Figure 2 is a longitudinal section through one form of construction of a tube-head in diagrammatical representation, the adjacent portions of the steam pipes. being shown in side-view. Figure 3 is a similar illustration showing a modified form of execution. Figure 4 is also a similar illustration and shows a third form of construction. The boiler illustrated in Figure 1 and the tube-heads illustrated in Figures 24 are mere eX- amples. I wish it to be understood that also other tubular boilers may be provided with superheaters of the novel kind, and

the smoke tubes need not be at an wide ones, as in the upper half 0 Figure 1, but all smoke tubes may be narrow, as in the lower half of this figure, the diameter of the tube heads being then chosen appropriate to the width of the smokeor fire-tubes.

Referring to Figure 1, b and c are ordinary superheating tubes which are connected at the furnace end not by an ordinary return bend, but by tube-heads a which are the main superheating members owing to their construction, as well as to their position, viz, in the hottest, zone of the smokeor fire-tubes. The length of the steam-way in such a tube-head is comparatively long, as appears, for instance, from Figure 2, where the tube-head consists of a closed casing 6 containing a spirally shaped tube a which contacts at its outer circumference with the metallic wall of the casing e. The other portion of the space of the casing forms also a spirally shaped steam passage. The steam that has made its way through the tube 6 flows through the spiral a into the casing e and then back through the spirally shaped passage to and into the tube 0 where the arriving steam which is now highly superheated is conducted away to the respective chamber of the header. In the form of construction shown in Figure 3 there is but one spiral-way which is formed by a blade o that is wound around the end a of the tube 0. In Figure 4, however, two spiral-ways are formed by two blades a which are wound, one within the other, around a solid bar 7 arranged centrally in the easing 6. This is the preferred form' of execution, apart from the dimensions, especially the diameter of the casing.

I claim:

In a tubular boiler, the combination, with a plurality of smoke-tubes, of superheating elements located within them and consisting each, firstly, of a superheating tubehead consisting of a closed casing located within the smoke-tube near to its furnace end, and of two spirally shaped blades wound one within the other, forming two rate steam-passages running one within the other and being connected with each other at the furnace end of the said casing; and secondly, of two straight tubes connected with 5 the said steam-passages, extending through the other portions of the smoke-tubes and connecting the said passages with the two header spaces.

WILHELM WI ILF.

Witnesses OTTO WULF, THoMAs NIULBE. 

